The winding of collector motor inductors or shaded-pole stators is carried out by two main methods:
A. by building up the coils on formers and then transferring them on to the poles by hand; PA1 B. by winding the wire directly on to the previously insulated stator by means of needle-type or other machines.
For mass production purposes, use is generally made of the second of these methods on account of its greater output.
The needle-type machines at present commercially available suffer from a number of disadvantages:
Their cost is high compared with the production that can be achieved with them, since only two stators can be wound at the same time.
Their use is limited exclusively to winding the wire on the stator, and they cannot be employed for carrying out additional associated operations.
Oil leakage occurs at the joint between the sleeve of the case enclosing the mechanism and the tool to which reciprocatory movement is imparted and which passes through the sleeve, and through the bore of which the wire is fed.
To change the angle of oscillation of the needle (for 2, 4, 6, 8 etc. poles), it is necessary to carry out operations which call for lengthy and careful work on the part of qualified personnel.